DE2259196C3 - Process for accelerating the conversion of epoxy compounds - Google Patents

Description

55 \ S

R " X

wherein R and R 'are identical or different radicals from the group H, alkyl, aryl, aralkyl, alkaryl, cycloalkyl and heterocyclic radical, halogen, keto, amino and nitro groups as well as ether, thioether, ester and Carbonamide moieties. containing radicals and 2 R can be sulfur or oxygen, R "is an alkynyl, Is alkylene, arylene, aralkylene or cycloalkylene radical, which is optionally substituted by halogen, nitro or amino groups, furthermore 2 connected by oxygen, nitrogen or sulfur, denotes identical or different R ″ groups, and X denotes hydrogen or a

R-C-

-C - R residue

R'-N N

\ r

65 is, in amounts of 0.05 to 10 wt .-%, preferably 0.5 to 5 wt .-%, based on the total amount of

Starting compounds, optionally together with known accelerators, used

Suitable imidazoBn derivatives for the purposes of the invention, which correspond to the general formula described earlier are, for example, those with optionally aryl-substituted alkyl radicals, with optionally alkyl-substituted aryl radicals and those that have a Alkylene or arylene bridge a second imidazoline group included how

2-methylimidazoline, 2,4 ^ dimethylimidazoline,

2-methyl-4- (n-butyl) imidazoline,

2-ethyimidazoline,

2-ethyl-4-methylimidazoline,

2-benzyl-imidazoline, 2-phenyl-imidazoline,

2-PhenyI-4- (N-morpholinyImethyl) -imidazoline, 2- (o-toyl) imidazoline,

2- (p-ToIyI) -imidazoI; n,

Tetramethylene-bis-imidazoline,

! , 1, j-TriiTiethy! -1,4-tetramethyien-bisimiclazoline,

133-trimethyl-1,4-tetramethylene-bisimidazoline,

1.l ^ -trimelhyl-l ^ -tetramethylene-bis-4-methylimidazoline,

133-trimethyl-1,4-tetramethylene-bis-4-methylimidazoline,

Phenylene-1,2-bis-imidazoline,

Phenylene-1,3-bis-imidazoline, Phenylene-1,4-bis-imidazoline, and

Phenylene-1 ^ -bis ^ -methylimidazoline. Mixtures of the imidazoline derivatives can also be used according to the invention.

The imidazone derivatives which can be used according to the invention can be prepared from optionally substituted geminal diamines and aliphatic diamines by known processes or aromatic mono- or dinitriles in the presence of elemental sulfur or furfuryl chloride can be produced as a catalyst.

From the large number of epoxy compounds which avoided —OC — O — CO groupings Compounds that can be implemented are: The epoxides from one or more times unsaturated hydrocarbons:

Ethylene, propylene, butylene, butadiene, cyclohexene, vinylcyclohexene, dicyclopentadiene,

Cyclododecatriene, polybutadienes, styrene; halogen-containing epoxides such as epichlorohydrin; Epoxy ethers of simple alcohols:

Methyl, ethyl, butyl, 2-ethylhexyl alcohol; Epoxy ethics of polyvalent alcohols:

Ethylene, propylene, butylene glycol,

Polyglycols, glycerine, pentaerythritol; Epoxy ethers of monohydric and polyhydric phenols:

Phenol, cresol, resorcinol, hydroquinone, 4,4'-dihydroxydiphenyl,

4,4'-dihydroxydiphenylmethane, 2,2-bis (4-hydroxyphenyl) propane, 4,4'-dihydroxydipnenyl sulfone,

Phenol-formaldehyde condensation products; N-containing epoxies:

the Ν, Ν-diglycidylaniline,

N, N'-dimethyl-diglyci <lyI-4,4'-diamino-

diphenylmethane. b5

Those which have more than one epoxy group in the molecule are preferred.
Mixtures thereof, for example those of mono- and polyepoxides or also epoxy compounds, can be used just as well as the pure epoxy compounds. conditions are implemented in the presence of solvents or plasticizers according to the process according to the invention. : '... ■

To. the compounds which contain one or more —OC — O — CO groupings include the Anhydrides of the aliphatic, cycloaliphatic !!, araliphatic, aromatic, aromatic and heterocyclic acids and, if appropriate, mixed acids Anhydrides.

The solid imidazolines are expediently in so-called solubilizers before use dissolved As solubilizers, common solvents for the solid imidazolines can be used as well as liquid imidazolines, liquid amines, imines, acids and anhydrides.

When using the imidazolines described above as curing accelerators for epoxy resins it turns out that end products can be obtained whose dimensional stability under heat is not insignificant is higher than when using piienols or Phenol derivatives or the tertiary amines described above, the N-unsubstituted imidazoline derivatives give about 20% higher values than the N-substituted ones. There are clear effects in comparison to the use of imidazole derivatives. Also increases the service life of the resin-hardener system at a setting temperature of 80 ° C almost doubled compared to the use of the other known curing accelerators.

The products manufactured using the process described represent moldings, coatings, Paints and adhesives with valuable properties represent, the mixtures depending on the intended use customary fillers, pigments, dyes and plasticizers are added to the reaction can. The compounds produced by reacting with monoepoxides are valuable products for the manufacture of textile auxiliaries and plastic products represent.

The following examples are intended to illustrate the effectiveness of the use according to the invention of the imidazoline derivatives described. In the examples, combinations of an epoxy resin, ie a diglycidyl ether of 2,2-bis- (4-hydroxyphenyl) propane with an epoxy value of 0.53, with various liquid or solid acid anhydrides (Examples 1-7 ) used. The effectiveness of the reaction accelerator used in the life of the resin-hardener systems in Geüertemperatur of 8O ⁰ C was fair.! the viscosity is controlled (example 1 + 7), the effectiveness on the properties of the cured end products was determined by determining the dimensional stability under heat according to Martens (DIN 53 458) (example 2-7). For this purpose, epoxy resin and anhydride were mixed in an equivalent ratio of 1: 1 and poured into appropriate molds. 0.5% by weight of reaction accelerator (based on the total amount of Harz-Hirter) were previously added to the anhydride. The castings were then pre-cured at 8O ⁰ C and cured at 100 ° C in a drying cabinet.

The following examples show the advantageous effect of the liquid used in accordance with the invention Imidazoline derivatives on the useful life of the resin-hardener systems as well as on the properties of the clearly recognizable hardened end products.

example

The epoxy resin was combined with methyl hexahydrophthalic anhydride (MHHPSA). It became the useful life at a temperature of 80 ° C determined:

Reaction accelerator

Service life at 80 ⁰ C

1 a 2,4,6-tri- (dimethyl-aminomethyl) phenol

Ib benzyl-dimethyl-amine

Ic 4- (n-butyl) imidazole

1 d 2-methyl-4- (n-butyl) imidazoline

1 e 2-Phenyl-4- (N-morpholinyl-methyl) -imidazoline

1 f 2-ethyl-4-methyl-imidazoline

57 minutes

68 minutes

75 minutes

108 minutes

120 minutes

141 minutes

The attached figure shows the time dependence of the viscosities of the combinations mentioned in this example in graphic form.

example

Epoxy resin as described and MHHPSA were combined according to Example 1. Has been pre-gelled 90 or 120 minutes at 80 ⁰ C, 240 minutes cured at 100 ^a, J. The Martens heat resistance values found were as follows:

TO

Reaction accelerator Gel time Worth it

2a 2,4,6-tri- (dimethyl-aminomethyl) -phenol

2b benzyl dirriethyi'smir,

2c 4- (n-butyl) imidazole

2d 2-methyl-4- (n-butyl) imidazoline

2e 2-phenyl-4- (N-morpholinyl-methyl) -imidazoline

2f 2-ethyl-4-methyl-imidazoline

Epoxy resin and MHHPSA were combined as described. Was Vcrgeliert was 90 or 120 minutes at 80 ° C, cured for 120 minutes at 100 ⁰ C.

Dl 90 min. 84 ⁰ C 90 min 07O / - 90 min. 110 ° C 120 min. .115 ⁰ C dazolin 120 min. 109 ⁰ C 90 min. 119 ° C Example 3

Reaction accelerator

Gel time

Worth it

3 a 2,4,6-tri- (dimethyl-aminomethyl> phenol

3 b benzyl-dimethyl-amine

3 c 4- (n-ButyI) imidazole

3d 2-methyl-4- (n-butyl) imidazoline

3 e 2-Phenyl-4- (N-morpholinyl-methyI) -in jidazoline

3f 2-EthyI-4-methyl-imidazoline

90min.

90 min.

90 min. 120 min. 120 min.

90 min.

83 ° C 81 ° C 108 ⁰ C 108 ⁰ C 107 ⁰ C 116 ° C

Example 4

The epoxy resin described was combined with hexahydrophthalic anhydride (HHPSA). Has been pre-cured for 90 minutes at 8O ⁰ C, hardened IZO minutes at 100 ° C.

Reaction accelerator Marlworth

4 a 2,4,6-tri- (dimethyl-aminomelhyl) -phenol 106 ⁰ C

4b Benzyl-dimethyl-amine 102 ⁰ C

4c 4- (n-butyl) -imidazoI 120 ⁰ C

4d 2-methyl-4- (n-butyl) -imidazoline 125 ⁰ C

4e 2-PhenyI-4- (N-morphoIinyl-methyl) -imi (Jazolin 12O ⁰ C

4 Γ 2-ethyl-4-methyl-im; dazoIin 128 ° C

Example 5

The epoxy resin described was combined with methyl tetrahydrophthalic anhydride (MTHPSA). Has been pre-cured for 120 minutes at 80 ° C, cured for 120 minutes at 100 ⁰ C.

Martenswerl reaction accelerator

5a 2,4,6-tri- (dimethy! -Aminomethyl) -phenol 112 ° C

5b Benzyl-dimethyl-amine 112 ° C

5c 4- (n-butyl) imidazole 121 ° C

5d 2-methyl-4- (n-butyl) -imidazoline 126 ⁰ C

5e 2-Phenyl-4- (N-morpholinyl-methyl) -imidazoline 122 ° C

5f 2-ethyl-4-methyl-imidazoline 129 ° C

Example 6

The epoxy resin described was combined with MHHPSA; was pre-cured for 90 minutes at 80 ⁰ C and was cured for 60 minutes at 100 ⁰ C.

Reaction accelerator Martwert

6a 2,4,6-tri- (dimethyl-aminomethyl) -phenoI 83 ° C

6b Benzyl-dimethyl-amine 82 ° C

6c 4- (n-Butyl) -imidazole 107 ⁰ C

6d 2-ethyl-4-diethyl-imidazoline 114 ° C

Example 7

An epoxy resin, ie a diglycid ether of 4,4'-dihydroxydiphenyldimethyl methane with an epoxy value of 0.52. was combined with MHHPSA as described. Has been pre-cured for 90 minutes at 80 ⁰ C, hardened minutes at 100 ⁰ C:

Reaction accelerator

7a 2,4,6-tri- (dim.ethyl-ainomethyl> phenol

7 b Benzyl-dimethyl-amm

7c 4- (n-butyl) imidazole

7d 2-phenyl-4- {N-morpholinyl-methyl> imidazoline

7e 2-ethyl-4-methy] imidazoline

Service life Worth it at 80 ⁰ C 82 min. 100 ⁰ C 97 min. 98 ° C 79 min. 119 ° C 147 min. 125 ° C 107 min. 123 ° C

1 sheet of drawings

Claims (1)

Claim:: Process for accelerating the conversion of monoepoxy compounds or epoxy compounds with more than one epoxy group in the molecule with compounds that contain one or more OC — O — CO groupings contain, thereby characterized in that the accelerator used is imidazoline derivatives of the general formula R. -C-R R'-N N \ f wherein R and R 'are identical or different radicals from the group H, alkyl, aryl, aralkyl, alkaryl, Cycloalkyl and heterocyclic radical, halogen, keto, amino and nitro groups as well as ether, Radicals containing thioether, ester and carbonamide groups and 2 R sulfur or oxygen can be «, R" is an alkynyl, alkylene, arylene, aralkylene or cycloalkylene radical, which is optionally by halogen. Nitro or amino groups is substituted, also 2 by Siwsrstoff, nitrogen or Sulfur connected, identical or different R ″ groups and X denotes hydrogen or a 15 95455, p. 10), tertiary amines, quaternary salts Ammonium compounds, Sn- (H) -SaIZe and alkali alcoholates, are also used as accelerators Salts of hydrofluoric acid and its complexes with inorganic or organic components has been described. It is widely known as To use reaction accelerators imidazole derivatives. The known accelerators could in practice not always the multiple requirements suffice. So was z. B. observed in the epoxy resin acid anhydride system, which are accelerated by phenol derivatives or tertiary amines, that the useful life of such a system is ^{relatively short at a gelling temperature of 80 0} C, whereby one -.j means period of use as the period in which the epoxy-acid anhydride accelerator system reaches a viscosity of 1500 cP, i.e. H. in which it is still is pourable. In addition, when using phenol derivatives or tertiary amines endpro products that do not have optimal dimensional stability in of heat. The aim was therefore to find accelerating substances that do not have these disadvantages own. It has now surprisingly been found that the reaction of monoepoxy compounds or epoxy compounds with more than one Epoxignippe in the molecule with compounds that contain one or more —OC-O — CO groups without accelerating the disadvantages described can, if one imidazoline derivatives of the general formula R. R-C- -C — R radical R'-N N \ f is, in amounts of 0.05 to 10 wt .-%, based on the total amount of the starting compounds, optionally together with known accelerators liked, used. It is known to react epoxy compounds with one or more than one epoxy group in the molecule with compounds that have one or more —OC-O — CO groupings contain. This implementation can - regardless of the nature of the used epoxy compound and the other reactant - proceed at very different rates. Since in many cases a quick If the reaction is extremely desirable, the aim is to accelerate this reaction by means of appropriate additives. So far, phenol has been used as accelerating additives and derivatives of phenol are preferred, such as the well-known 2,4,6-tris (dimethylaminomethyl) phenol (DE-OS R-C-R'-N R. -C-R 40 45